A Guardian journalist has caused a Twitter storm after a Telegraph journo used the word 'nutjob' to describe Jeremy Corbyn's new Shadow Chancellor, John McDonnell.

Tweeting to her 74,000 followers, Hannah Jane Parkinson said that the headline had "irresponsible word choices", and was just another in a long line that stigmatised or trivialised mental health conditions.

The headline in the midst of the storm, 'Corbyn has just appointed a nutjob as Shadow Chancellor', was defended by the journalist who penned it, Jeremy Warner, and MP Douglas Carswell.

Parkinson chronicled her argument on Storify, writing: "[I] went on a tweet storm after the latest irresponsible use of language around mental health (this time in the Telegraph, but not limited to that paper by any means).

"It's really important that mainstream media pay attention to the impact language around mental health and illness has."